Branch pieces for providing branch connections in a pipe are known in which the first and second parts are interconnected by two wedge-shaped members which engage with corresponding formations on the two parts on either side of the pipe. However the operation of mounting the two wedge-shaped members on the two parts presents certain difficulties. After the first and second parts are disposed on the pipe and held fast, one of the wedge-shaped members is applied, and then it is first necessary to ensure that the two parts are properly aligned opposite each other before the second wedge-shaped member is applied.
It is known to overcome this difficulty by hingedly connecting the two parts of a branch piece together, but this form of construction is more expensive to manufacture. Furthermore, a hole of considerable size is required at the location of the branch connection, in order that after the first part is disposed on the pipe the second part can be pivoted around the pipe into position.